Conventionally, a valve timing adjusting device is provided to an internal combustion engine. In one example, a valve timing adjusting device is coupled to a crankshaft of an internal combustion engine via a chain and is further connected to one end of a camshaft. The valve timing adjusting device is configured to vary a relative rotational phase between the crankshaft and the camshaft thereby to enable to vary timings of opening and closing of an intake valve and/or an exhaust valve of the internal combustion engine.